The invention relates to an apparatus for operating the roof panel of a sliding roof or a sliding/tilting roof, comprising a motor for moving the roof panel, a control unit for energizing the motor and a setting means for setting a desired position of the roof panel.
Such an apparatus is for example known from DE-A-33 24 107. In this known apparatus a closed loop control system is used, wherein the position of the roof panel is continuously measured and the motor is energized until the actual position equals the desired position. Although a good operation of the roof panel is possible with this known apparatus, special measures must be taken in view of the closed loop control to avoid instabilities. To this end the known apparatus is provided with a hysteresis circuit to avoid instabilities around the desired position of the roof panel. Thereby the known apparatus is relatively complicated.
The invention aims to provide a simplified apparatus of the above-mentioned type, by which a sufficiently accurate positioning of the roof panel in the desired position is nevertheless possible.